From a British correspondent:
Hi! I ordered the paper copy of your algebra book on the net as a second hand book.
Last year my niece was struggling with maths and I used your book as a resource for teaching and this year she has scored 100%.
What a great book and concepts of teaching. Such an integrated approach is exemplary and I CANNOT THANK YOU ENOUGH.
KEEP IT COMING.
I am glad that I found an electronic version now. Thanks a lot.